The use of charge storage means or capacitors in conjunction with electronic circuitry for timing functions is well-known.
In many flame safeguard or burner control applications, timers are used for various timing functions such as prepurge, trial for ignition, ignition, etc. A malfunctioning timer or timing out of proper sequence in this type of an application can provide a time interval which will create a major safety hazard and potentially an explosion at the fuel burner. A means of safestart check is required in these applications to assure the proper output state of all times at the start of each burner cycle. However, a safe start check along does not assure that a timer will not operate out of sequence later in the operation cycle. As such, capacitive operated timers require extensive safety circuitry in these applications.